999 gold is almost pure (99.9%). Some gold coins, bars and grain is .999 fine, not to be confused with the UK emergency telephone number 999, although gold is good in an emergency.
To calculate the carat (or karat) equivalent of .999 gold, simply multiply 24 by .999 = 23.976 carats.
Which are Which?
Different Standards of 24 Carat Gold Coins
The original "pure gold" bullion coins were Canadian maples. From their first date of issue in 1979 for four years up to 1982 inclusive, gold maple leaves were made of .999 fine gold (99.9). Only from 1983 onwards were they changed to .9999 (99.99) pure. The difference is only very slight indeed, but we are trying to be pedantically accurate here!
Manx nobles were also made in two different standards, 22 carat gold from 1984 to 1988 inclusive, and .9999 gold from 1994 onwards. Manx gold crowns have been made in wide variety of sizes and gold alloys, too many to try to analyse here, but most of the one ounce and fractional bullion versions were produced in .9999 gold.
In addition British Sovereigns are made of 22 carat gold, and although they predate the concept of a one ounce coin, are an excellent, but often overlooked alternative. Many other, older gold coins were made of .900 gold including French and Swiss, but this does not reduce their value to the investor.
These older coins were originally intended for circulation, and they were made in sizes and weights which suited their original purposes many years ago. Sovereigns were first issued in 1489, and have retained their current format since 1817. There are advantages and disadvantages in buying these "real" coins instead of modern bullion coins.
The minimum accepted standard for gold coins to be treated as VAT free investment gold in the EU is 900 parts per thousand, equivalent to 21.60 carats.
You may wish to view all of our articles on our gold guide